<div class="container">
    <div style="margin-top:50px;" class="col-md-4 col-md-offset-3 col-sm-6 col-sm-offset-2">
        <div style="padding-top:30px">
            <form name="validateForm" class="form-horizontal">
                <div style="margin-bottom: 25px" class="input-group">
                    <span class="input-group-addon"><i class="glyphicon glyphicon-user"></i></span>
                    <input type="text"
                           class="form-control"
                           ng-model="vm.username" required />
                </div>

                <div style="margin-bottom: 25px" class="input-group">
                    <span class="input-group-addon"><i class="glyphicon glyphicon-lock"></i></span>
                    <input type="password"
                           class="form-control"
                           ng-model="vm.password" required />
                </div>

                <div class="form-group">
                    <div class="col-sm-12 controls">
                        <button class="btn btn-success"
                                ng-disabled="validateForm.$invalid"
                                ng-click="vm.login()">
                            Sign in
                        </button>
                    </div>
                </div>
            </form>
        </div>
    </div>
</div>